How to build a ultra high frequency speaker for bats

[TheBlackBat]

Hi,

I'm new to this whole game but was wondering if there is someone who can point me in the path of what's needed and how to built it. As I like to make stuff this is a new skill for me to try.

But also trying to get two birds with one stone. The other stone is that I'm trying to build an acoustic lure to try and entice bats into a net, as I do bat conservation. As when you play a distress/social call of a bat they come and investigate which is when we catch them. This helps us identify bats to help with conservation.

This what you normally have to buy:

http://binaryacoustictech.com/batpages_files/at100.htm

But as you can see it isn't cheap and conservation work isn't paid well at all. It has to be able to produce sound up to 70kHZ to be effective with a transmission power of100 dB SPL @ 1m . I was trying to see if possible to adapt a dog deterrent or make one similar but where I can play recording rather than pulse. Ideally needs to be small and work for 30minutes to an hour plus with out burning up, which I read with some transmitters.

So with the use of a laptop to produce the file out put of what are the next steps.

Thanks

 

[Harald Kapp]

The transducer can be bought very cheaply e.g. here.

So with the use of a laptop to produce the file out put

Neither is a standard pc sound file able to reproduce 70 kHz audio, nor is standard pc hardware able to reproduce a 70 kHz output.
You will need specialized hardware for this task.
Where does your recording come from?

 

[Audioguru]

Some cheap tweeters are advertised to deliver ultrasonic power but they have no spec's and probably do not produce ultrasonic sounds, just a little heat instead.

The piezo transducers probably produce only a narrow range of frequencies near resonance. Bats will think it is a truck backing up and run away.